Copiapo , Chile -LRB- CNN -RRB- -- Some of the families camped outside the San Jose mine , waiting for rescuers to reach 33 workers trapped underground , fear Chilean President Sebastian Pinera may be playing politics with the rescue operation in an effort to boost his popularity .

Pinera visited the mine Sunday and spoke with the trapped workers . He also presented their families with a copper plate engraved with the words miners first used to tell rescuers they were alive , `` We 're fine , in the shelter , all 33 . ''

`` This is all politics . It 's dirty . It 's trickery and propaganda . They 're playing with the feelings of our loved ones , '' said Nelly Bugueno , mother of trapped miner Victor Zamora .

The mine rescue appears to have boosted Pinera 's popularity at a time when he was under fire in other parts of the country .

In the south of Chile , Pinera is battling a hunger strike by 34 Mapuche Indians , part of the indigenous group 's ongoing campaign for independence .

Along the central and southern coast , some Chileans accuse the government of being too slow to rebuild after the February earthquake and tsunami .

But his overall approval rating surged to 56 percent in August , according to a survey by Adimark GfK , a 10 percent increase over the July numbers . The Chilean research company said the increase was `` directly related with the rescue operations of the trapped miners in the San Jose mine . ''

When the workers first sent word that they were alive , Pinera triumphantly waved their written note before television cameras . Sunday was his fifth visit to the mine .

Outside the mine Sunday , some family members said they were angry that the rescue effort was being turned into a political spectacle .

`` We know politicians want to show off , but I do n't care about the politics . All I care about is that the president gets our boys out , '' said Cristina Nunez , wife of miner Claudio Yanez .

The sister of another trapped miner accused rescuers of delaying the switch-on of a recently-assembled oil rig -- the so-called Plan C drill -- until Pinera arrived Sunday .

She also claimed rescuers discovered the miners were alive in an underground shelter in the early hours of August 22 , but waited until midday to officially announce the news , after Pinera arrived at the mine .

She declined to be named for fear of losing her job for anti-government comments .

`` We 're still not free in Chile to speak our mind , '' she said .

Another woman , the wife of one of the miners , said families were sometimes not given information in a timely fashion . The woman , who asked not to be named for fear of unspecified reprisals , said she did not bother to wait in the hot sun to meet the president Sunday .

`` I got tired of waiting and I 'm bored of the way he 's doing things . The mining minister and the rescuers have done a good job , but the president is playing with us , '' she said .

Not all relatives , however , felt frustrated by political overtones in the rescue effort .

`` We have to be calm . God works on his own schedule and we have to wait patiently , '' said Eli Steger , daughter of trapped miner Jose Ojeda .

The president arrived at the mine at midmorning Sunday , flying in on a military helicopter that landed in the desert , kicking up dust . He spent about an hour and a half at the mine .

He met 5-day-old Esperanza Ticona , the daughter of Ariel Ticona , one of the trapped miners -- and kissed her in front of television cameras . Esperanza was brought to the mine for the first time Sunday by her mother , Elizabeth Segovia .

Watch how miners ' families marked independence day

`` Hopefully this spirit of unity , faith , confidence and pride to be Chilean that is in the air at the San Jose mine and in every corner of Chile is a spirit that will illuminate this third century of independence , '' Pinera said , referring to Chile 's recent bicentennial celebration .

Away from reporters , Pinera first visited a powerful oil drill that has been transported to the mine to assist in the rescue . The drill , known as Plan C , began operating Sunday . Mine experts say it could be the fastest way of punching through rock a hole that is wide enough to hoist the miners back to the surface .

Two other drills , a Schramm T-130 -LRB- Plan B -RRB- normally used for boring water holes and a Raise Borer Strata 950 -LRB- Plan A -RRB- normally used for drilling ventilation chimneys in mines , have been operating for about three weeks .

Sunday was the first day that all three drills were working simultaneously , Pinera said .

@highlight

Pinera is battling a hunger strike by 34 Mapuche Indians in south of Chile

@highlight

Research firm says the rescue operation has boosted Pinera 's approval ratings

@highlight

Sunday 's visit is his fifth to the mine

@highlight

He presents families with gift , meets five-day-old Esperanza Ticona , miner 's daughter